From d31d0044a3e154db5e45985c5e6ba9309e43f143 Mon Sep 17 00:00:00 2001
From: erickahmed <engineering@erickahmed.com>
Date: Tue, 22 Apr 2025 20:24:44 +0200
Subject: [PATCH] Refactore code: global and geometry variables now more clear,
 stacking function easier to read

---
 venturi/de-lavale-duct.scad | 88 -------------------------------------
 venturi/venturi.scad        | 59 +++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 88 deletions(-)
 delete mode 100644 venturi/de-lavale-duct.scad
 create mode 100644 venturi/venturi.scad

diff --git a/venturi/de-lavale-duct.scad b/venturi/de-lavale-duct.scad
deleted file mode 100644
index 7499545..0000000
--- a/venturi/de-lavale-duct.scad
+++ /dev/null
@@ -1,88 +0,0 @@
-// Inlet variables
-inlet_length  = 250; // 100.5 raggio grande, 200mm lunghezza
-inlet_radius  = 200;
-inlet_throat_radius = 100;
-inlet_thickness     = 0.25;
-inlet_segments      = 30;  // Number of stacked layers (higher = smoother)
-inlet_curve_factor  = 2;   // Controls how aggressively the walls curve
-
-module inlet() {
-    difference() {
-        union() {
-            for (i = [0:inlet_segments-1]) {
-                h = inlet_length / inlet_segments;
-                t = i / (inlet_segments-1);
-                
-                // Apply power function for curvature
-                r1 = inlet_throat_radius + (inlet_radius - inlet_throat_radius) * pow(t, inlet_curve_factor);
-                r2 = inlet_throat_radius + (inlet_radius - inlet_throat_radius) * pow((i+1) / (inlet_segments-1), inlet_curve_factor);
-
-                translate([0, 0, i * h])
-                cylinder(h = h, r1 = r1, r2 = r2, $fn = 75);
-            }
-        }
-
-        // Inner subtraction (to maintain thickness)
-        union() {
-            for (i = [0:inlet_segments-1]) {
-                h = inlet_length / inlet_segments;
-                t = i / (inlet_segments-1);
-                
-                r1 = (inlet_throat_radius + (inlet_radius - inlet_throat_radius) * pow(t, inlet_curve_factor)) - inlet_thickness;
-                r2 = (inlet_throat_radius + (inlet_radius - inlet_throat_radius) * pow((i+1) / (inlet_segments-1), inlet_curve_factor)) - inlet_thickness;
-
-                translate([0, 0, i * h])
-                cylinder(h = h, r1 = r1, r2 = r2, $fn = 75);
-            }
-        }
-    }
-}
-
-// Rotate for correct orientation
-rotate([0, -90, 0]) inlet();
-
-
-
-
-// Outlet variables
-outlet_length  = 350;
-outlet_radius  = 165;
-outlet_throat_radius = 100;
-outlet_thickness     = 0.25;
-outlet_segments      = 20;  // Number of stacked layers (higher = smoother)
-outlet_curve_factor  = 1.5;   // Controls how aggressively the walls curve
-
-module outlet() {
-    difference() {
-        union() {
-            for (i = [0:outlet_segments-1]) {
-                h = outlet_length / outlet_segments;
-                t = i / (outlet_segments-1);
-                
-                // Apply power function for curvature
-                r1 = outlet_throat_radius + (outlet_radius - outlet_throat_radius) * pow(t, outlet_curve_factor);
-                r2 = outlet_throat_radius + (outlet_radius - outlet_throat_radius) * pow((i+1) / (outlet_segments-1), outlet_curve_factor);
-
-                translate([0, 0, i * h])
-                cylinder(h = h, r1 = r1, r2 = r2, $fn = 75);
-            }
-        }
-
-        // Inner subtraction (to maintain thickness)
-        union() {
-            for (i = [0:outlet_segments-1]) {
-                h = outlet_length / outlet_segments;
-                t = i / (outlet_segments-1);
-                
-                r1 = (outlet_throat_radius + (outlet_radius - outlet_throat_radius) * pow(t, outlet_curve_factor)) - outlet_thickness;
-                r2 = (outlet_throat_radius + (outlet_radius - outlet_throat_radius) * pow((i+1) / (outlet_segments-1), outlet_curve_factor)) - outlet_thickness;
-
-                translate([0, 0, i * h])
-                cylinder(h = h, r1 = r1, r2 = r2, $fn = 75);
-            }
-        }
-    }
-}
-
-// Rotate for correct orientation
-rotate([0, 90, 0]) outlet();
\ No newline at end of file
diff --git a/venturi/venturi.scad b/venturi/venturi.scad
new file mode 100644
index 0000000..9e9ae49
--- /dev/null
+++ b/venturi/venturi.scad
@@ -0,0 +1,59 @@
+// ======== Global Parameters ======== //
+$fn = 75;
+inlet_segments     = 60;
+outlet_segments     = 20;
+
+// ======== Venturi Geometry ======== //
+inlet_length   = 250;
+outlet_length  = 350;
+inlet_radius   = 300;
+throat_radius  = 80;
+outlet_radius  = 110;
+wall_thickness = 5;
+
+inlet_curve_factor  = 2;
+outlet_curve_factor = 1.5;
+
+// ======== Stacking Function ======== //
+module stacked_shell(length, r_end, thickness, segments, curve_factor, is_outer = true) {
+    for (i = [0:segments - 1]) {
+        h = length / segments;
+        t0 = i / (segments - 1);
+        t1 = (i + 1) / (segments - 1);
+
+        r1 = throat_radius + (r_end - throat_radius) * pow(t0, curve_factor);
+        r2 = throat_radius + (r_end - throat_radius) * pow(t1, curve_factor);
+
+        if (!is_outer) {
+            r1 = r1 - thickness;
+            r2 = r2 - thickness;
+        }
+
+        translate([0, 0, i * h])
+            cylinder(h = h, r1 = r1, r2 = r2);
+    }
+}
+
+// ======== Inlet Module ======== //
+module inlet() {
+    difference() {
+        union()
+            stacked_shell(inlet_length, inlet_radius, wall_thickness, inlet_segments, inlet_curve_factor, true);
+        union()
+            stacked_shell(inlet_length, inlet_radius, wall_thickness, inlet_segments, inlet_curve_factor, false);
+    }
+}
+
+rotate([0, -90, 0]) inlet();
+
+// ======== Outlet Module ======== //
+module outlet() {
+    difference() {
+        union()
+            stacked_shell(outlet_length, outlet_radius, wall_thickness, outlet_segments, outlet_curve_factor, true);
+        union()
+            stacked_shell(outlet_length, outlet_radius, wall_thickness, outlet_segments, outlet_curve_factor, false);
+    }
+}
+
+rotate([0, 90, 0]) outlet();
\ No newline at end of file